WASHINGTON – AAA reported that the national average gasoline price increased earlier this week to $3.40. The organization said this price is still 12 cents below the price a month ago, 28 cents less than the price a year ago, and 54 cents less than the year-to-date peak average price of $3.94 in April.

Gasoline prices have been slowly climbing recently, which mirrors what occurred last July, according to AAA. In 2011, gasoline prices went up 17 cents during July and stayed high through Labor Day before declining. By comparison, so far in July, prices were up 7 cents as of July 16.

According to AAA, gas prices are rising because oil prices have been increasing. The price of West Texas Intermediate (WTI) crude oil increased by $1.33 per barrel to a price of $88.43 at the close of formal trading on the NYMEX exchange on July 16. For the sake of comparison, this is the highest price since May 29 (when it closed at 90.76 per barrel), AAA stated.

On a regional basis, the least expensive gasoline is in South Carolina, at an average price of $3.05, as of July 16 ($3.10 as of July 19, according to GasBuddy.com). The highest price in the continental U.S. is California, with an average of $3.72 as of July 16 ($3.73 as of July 19, according to GasBuddy.com).

Factors affecting crude oil prices, driving them up, during the last few weeks include new sanctions against Iran and that country’s threats to close the Strait of Hormuz, a primary oil shipping route. Also, AAA stated that better economic data than expected from China helped put pressure on demand, as signs of strong economic growth generally lead to higher oil prices.